Associations of pyrethroid exposure with bone mineral density and osteopenia in adults.

INTRODUCTION: This study was to investigate the correlations between pyrethroid exposure and bone mineral density (BMD) and osteopenia. MATERIALS AND METHODS: This cross-sectional study included 1389 participants over 50 years of age drawn from the 2007-2010 and 2013-2014 National Health and Nutrition Examination Survey (NHANES). Three pyrethroid metabolites, 3-phenoxybenzoic acid (3-PBA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid (trans-DCCA), and 4-fluoro-3-phenoxybenzoic acid (4-F-3PBA) were used as indicators of pyrethroid exposure. Low BMD was defined as T-score < - 1.0, including osteopenia. Weighted multivariable linear regression analysis or logistic regression analysis was utilized to evaluate the correlation between pyrethroid exposure and BMD and low BMD. Bayesian kernel machine regression (BKMR) model was utilized to analyze the correlation between pyrethroids mixed exposure and low BMD. RESULTS: There were 648 (48.41%) patients with low BMD. In individual pyrethroid metabolite analysis, both tertile 2 and tertile 3 of trans-DCCA were negatively related to total femur, femur neck, and total spine BMD [coefficient (ß) = - 0.041 to - 0.028; all P < 0.05]. Both tertile 2 and tertile 3 of 4-F-3PBA were negatively related to total femur BMD (P < 0.05). Only tertile 2 [odds ratio (OR) = 1.63; 95% CI = 1.07, 2.48] and tertile 3 (OR = 1.65; 95% CI = 1.10, 2.50) of trans-DCCA was correlated with an increased risk of low BMD. The BKMR analysis indicated that there was a positive tendency between mixed pyrethroids exposure and low BMD. CONCLUSION: In conclusion, pyrethroids exposure was negatively correlated with BMD levels, and the associations of pyrethroids with BMD and low BMD varied by specific pyrethroids, pyrethroid concentrations, and bone sites.

A Prospective Longitudinal Study of the Effects of Eslicarbazepine Acetate Treatment on Bone Density and Metabolism in Patients with Focal-Onset Epilepsy.

BACKGROUND AND OBJECTIVES: Eslicarbazepine acetate (ESL) is a third-generation anti-seizure medication for patients with focal-onset epilepsy. There are known short-term impacts of classic enzyme-inducing drugs on bone health. For oxcarbazepine, which like ESL is a less potent inducer of cytochrome P450 (CYP450) than carbamazepine, some studies have shown that treatment is associated with increased bone metabolic parameters. The effects of ESL on bone health have not been systematically evaluated so the objective of this study was to investigate whether adverse effects of ESL on bone mineral density (BMD) could be measured after a 12-month exposure period. In addition, the effects of ESL on bone turnover were investigated using laboratory indicators of bone metabolism. METHODS: BONAPARTE was a prospective, longitudinal, observational study that enrolled patients with focal-onset epilepsy with or without secondary generalization who started treatment with ESL, either as adjunctive treatment or monotherapy, at two tertiary epilepsy centres in Germany between February 2018 and July 2020. Standardised osteodensitometry and biochemical bone metabolism parameters at the time of ESL initiation and 1 year after continuation of therapy were assessed. Comparisons between biochemical and densitometric parameters at baseline and after 12 months of treatment were performed using the paired samples t test. RESULTS: In total, 26 patients (15 male; mean age 41.4 ± 12.5 years) newly treated with ESL were evaluated. Six of these patients had osteopenia at baseline. The mean daily dose of ESL at the 12-month follow-up was 1438 ± 1406 mg. At the group level, there were no significant effects of treatment with ESL on laboratory markers or on BMD. Mean values of BMD in g/cm2 at baseline and after 12 months of ESL treatment were 1.17 (± 0.16) and 1.16 (± 0.16) in the lumbar spine, and 0.98 (± 0.15) and 0.96 (± 0.15) in the proximal femur, respectively. Intra-individually, two patients developed de novo osteopenia measured at the femoral neck associated with relevant changes in bone metabolic parameters. CONCLUSION: Neither osteodensitometry nor bone metabolism parameters showed significant group effects after 1 year of treatment with ESL. Individual fluctuations were observed, however, which may warrant monitoring for longer follow-up periods. The study was registered in the German register for clinical studies under the number DRKS00010430 with the official name BONAPARTE.

Changes in bone turnover markers and bone modulators during abatacept treatment.

Rheumatoid arthritis (RA) causes bone loss, only partly related to inflammation. The impact of RA treatments on bone metabolism and their ability to mitigate bone loss remains uncertain. The primary goal of our study was to examine the influence of abatacept on serum levels of markers and regulators involved in bone turnover. Secondary objectives included evaluating changes in bone mineral density (BMD), bone health parameters, erosions, and exploring potential correlations among these parameters. We conducted a prospective observational study on patients with active seropositive RA failure to biological disease modifying anti-rheumatic drugs initiating treatment with abatacept. We measured at baseline and after 1, 2, 3, 6, 9 and 12 months: serum bone turnover markers (CTX, P1nP, B-ALP), bone modulators (Dkk-1, sclerostin, vitamin D, PTH, OPG and RANKL), BMD and radiographic parameters (modified Sharp van der Heijde score [mSvdH], bone health index [BHI] and metacarpal index [MCI]). Disease activity and glucocorticoid intake was monitored. 33 patients were enrolled in the study. We found a significant increase in markers of bone formation (B-ALP and P1nP) from baseline to M6 and M12. PTH increased significantly at M6 but not at M12. All other bone markers and modulators did not change. We found a significant decrease in BHI and MCI from baseline to M12 (median difference - 0.17 95% CI - 0.42 to - 0.10, p 0.001 and - 0.09 95% CI - 0.23 to - 0.07, respectively). BMD at femoral neck transitorily decreased at M6 (mean difference - 0.019 g/cm2 95% CI - 0.036 to - 0.001 p 0.04). BMD at total hip, lumbar spine and mSvdH score did not change significantly. P1nP delta at M12 correlated with delta mSvdH. Treatment with abatacept was associated with a significant increase in bone formation markers. The secondary and transient increase in PTH serum levels may be responsible of the transitory bone loss.

Association of a Polygenic Risk Score With Osteoporosis in People Living With HIV: The Swiss HIV Cohort Study.

BACKGROUND: Bone mineral density (BMD) loss may be accelerated in people with HIV (PLWH). It is unknown whether a polygenic risk score (PRS) is associated with low BMD in PLWH. METHODS: Swiss HIV Cohort Study participants of self-reported European descent underwent ≥2 per-protocol dual x-ray absorptiometry (DXA) measurements ≥2 years apart (2011-2020). Univariable and multivariable odds ratios (ORs) for DXA-defined osteoporosis were based on traditional and HIV-related risk factors and a genome-wide PRS built from 9413 single-nucleotide polymorphisms associated with low BMD in the general population. Controls were free from osteoporosis/osteopenia on all DXA measurements. RESULTS: We included 438 participants: 149 with osteoporosis and 289 controls (median age, 53 years; 82% male, 95% with suppressed HIV RNA). Participants with unfavorable osteoporosis PRS (top vs bottom quintile) had univariable and multivariable-adjusted osteoporosis ORs of 4.76 (95% CI, 2.34-9.67) and 4.13 (1.86-9.18), respectively. For comparison, hepatitis C seropositivity, 5-year tenofovir disoproxil fumarate exposure, and parent history of hip fracture yielded univariable osteoporosis ORs of 2.26 (1.37-3.74), 1.84 (1.40-2.43), and 1.54 (0.82-2.9). CONCLUSIONS: In PLWH in Switzerland, osteoporosis was independently associated with a BMD-associated PRS after adjustment for established risk factors, including exposure to tenofovir disoproxil fumarate.

Could Future Implant Failures be Predicted Based on Observed Bone Levels and Bone Loss After 5 Years? A Retrospective Investigation on Patients Presented in Previous Studies.

Purpose: To evaluate the diagnostic accuracy of bone loss/bone levels, as detected after 5 years of implant function, in identifying patients who suffered implant failures in the following 5 years. Materials and Methods: Data on radiographic measurements of marginal bone levels at prosthesis placement and after 5 years of function were retrospectively retrieved from 11 previous publications. Included patients were allocated into different subgroups with regard to bone loss/bone level during/after 5 years in function, respectively. A diagnostic test was used to estimate the accuracy of finding patients/jaws/implants at risk for a future implant failure by calculating sensitivity, specificity, positive predictive values (PPVs), and negative predictive values (NPVs) in different subgroups, respectively. Results: Altogether, 749 treated jaws (723 patients/3,363 implants) were included in the study group. Treated jaws in the high-level subgroups presented an overall higher risk of implant failures from 5 to 10 years in function (P < .05). Many treated jaws/implants were allocated into the high-level groups, but the proportions of implant failures were low in these groups. The diagnostic test comparing high- and low-level groups with and without implant failures showed low accuracy to predict implant failures; the PPV ranged from 4% to 33%. Lower PPVs were observed for diagnostic tests for individual implants (range: 4% to 6%). Conclusion: More severe bone loss was associated with higher risk of future implant failure. However, many patients/ implants with obvious bone loss in the study group and low prevalence of implant failures at the 10-year examination resulted in poor accuracy in identifying individual patients or implants at risk for failure. This suggests that it is difficult to predict future implant failures based only on radiographic measurements.

Discontinuation of denosumab in men with prostate cancer.

In patients with non-metastatic prostate cancer, treated with radiation therapy and androgen deprivation therapy for 3 years and DMAB on average for 5 years, BMD was in the normal or osteopenic range. Discontinuation of DMAB led to a bone loss of 2-5%. In men with osteopenia, the bone loss was prevented by zoledronate. PURPOSE: Patients with prostate cancer receiving androgen deprivation therapy (ADT) are treated with denosumab (DMAB) to prevent fractures and preserve bone mass. We wanted to investigate the change in BMD in men with non-metastatic prostate cancer discontinuing DMAB. METHODS: We conducted a retrospective cohort study based on medical records from patients referred to the Department of Endocrinology from the Department of Urology, Aarhus University Hospital between June 1, 2018, and June 1, 2021. We retrieved information on biochemistry and DXA performed 0-6 months after the last DMAB injection and a second DXA performed approximately 12 months after the first. In case of a BMD T-score ≤ - 1 at the lumbar spine or total hip at the first DXA, the patients were treated with zoledronate. The primary endpoint was change in lumbar spine BMD. RESULTS: We included 50 patients with non-metastatic prostate cancer. The mean DMAB treatment duration was 5 ± 0.1 years. Among the patients treated with zoledronate (n = 9), BMD was maintained at the spine and femoral neck after a mean of 16 months. We found a significant decrease in BMD; - 4.9 ± 4.2%, - 1.9 ± 3.5%, and - 2.4 ± 3.6% at the spine, total hip, and femoral neck between the first and second DXA in the patients not treated with zoledronate (n = 24) (p ≤ 0.01 for all). One patient who did not receive ZOL sustained multiple fragility vertebral fractures after DMAB discontinuation. CONCLUSION: In men with non-metastatic prostate cancer, discontinuation of DMAB after stopping ADT led to an average bone loss of 2-5%. Zoledronate prevented bone loss in men with osteopenia.

Atypical antipsychotics olanzapine and clozapine increase bone loss in female rats with experimental periodontitis.

BACKGROUND AND OBJECTIVES: Periodontitis is a highly prevalent disease in psychiatric patients, including those undergoing symptomatic treatment with second-generation antipsychotics. Some of these drugs, such as clozapine (CLO) and olanzapine (OLA), have prominent metabolic effects such as weight gain, hyperglycemia, and dyslipidemia, which are risk factors for periodontitis. In addition to the metabolic effects, there are reports of changes in salivary flow, gingival bleeding, and caries. In this context, we aimed to evaluate if the metabolic effects of OLA and CLO alter periodontal parameters in an animal model of periodontitis without the environmental and psychosocial biases inherent to human diseases. METHODS: In the first set of experiments, male and female adult Wistar rats received oral administration of CLO, OLA, or vehicle for 45 days. They were evaluated for body mass composition and weight gain, blood glucose parameters (fasting and glucose tolerance and insulin resistance tests), and lipid profile (HDL, total cholesterol, and triglycerides). In a second set of experiments, the same measurements were performed in female rats exposed to the antipsychotics for 45 days and ligature-induced periodontitis on the 30th day of treatment. Macroscopic measurements of exposed roots, microtomography in the furcation region of the first molar, and histological evaluation of the region between the first and second molars were evaluated to assess bone loss. Additionally, gingival measurements of myeloperoxidase activity and pro-inflammatory cytokine TNF-α were made. RESULTS: Only females exposed to OLA had more significant weight gain than controls. They also exhibited differences in glucose metabolism. Ligature-induced periodontitis produced intense bone retraction without changing the density of the remaining structures. The bone loss was even higher in rats with periodontitis treated with OLA or CLO and was accompanied by a local increase in TNF-α caused by CLO. These animals, however, did not exhibit the same metabolic impairments observed for animals without periodontitis. CONCLUSION: The use of clozapine and olanzapine may be a risk factor for periodontal disease, independent of systemic metabolic alterations.

One-Year Romosozumab Treatment Followed by One-Year Denosumab Treatment for Osteoporosis in Patients on Hemodialysis: An Observational Study.

There is limited evidence on the use of romosozumab (ROMO) in the treatment of osteoporosis in patients on hemodialysis (HD); thus, we aimed to investigate this topic. This prospective, observational, single-center cohort study included 13 prior osteoporosis treatment-naïve patients on HD with osteoporosis. They first received ROMO once monthly for 12 months (210 mg; subcutaneously once every month). Thereafter, they received denosumab (DENO) for an additional 12 months (60 mg; subcutaneously once every 6 months). We examined the incidence of new fractures; treatment safety; and temporal changes in the bone mineral density (BMD), bone metabolism markers, and vascular calcification. No new cases of fractures were noted. The median one-year percentage changes (from the baseline) in the BMDs at the lumbar spine (LS), total hip (TH), and femoral neck (FN) were + 9.0%, + 2.5%, and + 4.7%, respectively. These changes were maintained for 24 months. The corresponding relative changes from the baseline to 24 months thereafter were + 14.9%, + 5.4%, and + 6.5%, respectively. The percentage changes in TH BMD and FN BMD were negatively correlated with baseline BMD. Coronary artery and thoracic aorta calcification scores increased slightly from baseline to 12 months thereafter. However, fatal events (cardiovascular disease-associated and all-cause deaths) did not occur during ROMO treatment. Effectiveness of ROMO was better in patients who had severe osteoporosis with low TH BMD, low FN BMD, and high tartrate-resistant acid phosphatase 5b level at ROMO initiation.

A retrospective analysis of bone loss in tenofovir-emtricitabine therapy for HIV PrEP.

BACKGROUND: Tenofovir-Emtricitabine (TDF-FTC) is known to cause bone loss in about 1-3% of HIV treated patients. Current studies lack evidence in minority groups and long-term bone loss effects in PrEP patients. SETTING: To address the risk of osteopenia/osteoporosis in patients on TDF-FTC therapy for HIV PrEP and to address the breakthrough incidence of HIV. METHODS: A retrospective analysis was performed in Kaiser Permanente patients from 2012-2021. Patients on TDF-FTC for PrEP without any prior history of osteopenia/osteoporosis (N = 7698) were analyzed to determine the relationship between PrEP adherence and osteopenia/osteoporosis. Descriptive statistics and Cox proportional hazards model were used to compare and analyze patient characteristics between those who developed osteopenia/osteoporosis and those who didn't. RESULTS: 3% were found to have osteopenia/osteoporosis. Patients who developed osteopenia/osteoporosis were more likely to have a proportion of days covered (PDC) ratio ≥90%, older, had history of Hep B, DM, CVD, CKD, hypertension, and baseline eGFR ≥90 mL/min/1.73 m2. Kaplan-Meier curve showed the event-free rate of osteopenia/osteoporosis decreased with time, with a greater reduction in patients with high adherence. Survival analysis showed only PDC of ≥90% was significantly associated with the risk of osteopenia/osteoporosis when adjusted. No incidence of HIV infection was detected. CONCLUSIONS: This retrospective cohort analysis showed that TDF-FTC offered superior PrEP protection. Although high PrEP adherence ensured protection from HIV infection, it was significantly associated with a higher risk of developing osteopenia/osteoporosis. These findings suggest that routine check-ups for osteopenia/osteoporosis may be needed.

LEVELS OF SMOKING AND PERI­IMPLANT MARGINAL BONE LOSS: A SYSTEMATIC REVIEW AND META-ANALYSIS.

AIM: This systematic review and meta-analysis sought to determine if there was a significantly enhanced risk of peri­implant marginal bone loss (MBL) due to the increased number of cigarettes smoked per day. MATERIALS AND METHODS: Six databases, including Medline, Embase, Cochrane Library, Web of Science, Scopus, and ProQuest, were searched until February, 2021. The search terms "dental implant, oral implant, smoking, smoker, non-smoker, marginal bone loss and crestal bone loss" were used in combination to seek the articles providing data for MBL related to the smoking habit. Articles were excluded if the quantity of cigarettes smoked per day was not reported. Random-effects meta-analyses were used to pool the estimates of mean difference (MD) with 95% confidence intervals (CI). RESULTS: Eight studies were included for qualitative and 5 for quantitative synthesis. The meta-analyses revealed higher levels of MBL in patients who smoked <10 or >10 cigarettes/day than in non-smokers (<10: (MD -0.33, 95% CI -0.69-0.03 and >10: MD -0.58, 95% CI -0.96- -0.19). There was a significant risk of MBL between patients who smoked >10 and <10 cigarettes/day (MD -0.23, 95% CI -0.47-0.01). CONCLUSION: It seems the risk of MBL is steadily increasing as daily smoking increases.

Macromolecular Dexamethasone Prodrug Ameliorates Neuroinflammation and Prevents Bone Loss Associated with Traumatic Brain Injury.

Traumatic brain injury (TBI) is one of the leading causes of death and disability among children and young adults in the United States. In this manuscript, we assessed the utility of an N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-based dexamethasone (Dex) prodrug (P-Dex) in the treatment of TBI. Using a controlled cortical impact TBI mouse model, P-Dex was found to passively target and sustain at the traumatic/inflammatory brain tissue for over 14 days after systemic administration. The histological evidence supports P-Dex's therapeutic potential in ameliorating neuroinflammation and mitigating neurodegeneration. Behaviorally, the P-Dex-treated animals showed statistically significant improvement in balance recovery. A trend of neurological severity score improvement at the early time point post-TBI was also noted but did not achieve statistical significance. While probing the potential glucocorticoid side effects that may associate with P-Dex treatment, we discovered that the TBI mice develop osteopenia. Interestingly, the P-Dex-treated TBI mice demonstrated higher bone mineral density and better bone microarchitecture parameters when compared to free Dex and the saline control, revealing the osteoprotective effect of P-Dex in addition to its neuronal protection benefits post-TBI.

Bone densitometry in children with idiopathic nephrotic syndrome on prolonged steroid therapy: A tertiary multicenter study.

Long-term glucocorticoids administration inhibits bone mineralization and has a negative impact on basic cellular mechanisms that are critical in the development and maintenance of bone strength. Steroids can cause osteoporosis in children and have a negative impact on bone mineral content (BMC) and bone mineral density (BMD). We aim to determine the BMD of children with idiopathic nephrotic syndrome (INS) who are on corticosteroids therapy. This cross-sectional study included 90 patients on corticosteroids therapy and 50 apparently healthy age and sex-matched children served as a control group. Renal functions, bone biochemistry, and parathyroid hormone (PTH) were measured in patients and controls. BMD was measured at the lumbar spinal region (L2-L4) using Dual-energy X-ray absorptiometry (DEXA) scan in both patients and controls groups. Serum PTH, phosphorous, and alkaline phosphatase levels were significantly higher in patients than in controls. There was a statistically significant reduction in blood calcium levels in patients compared to controls. Osteopenia was diagnosed by DEXA scan in 24 patients (26.7%) and osteoporosis in 12 patients (13.3 %). There was a statistically significant decline in BMD-z score, BMD, and BMC in patients compared to the healthy group. Patients with INS on corticosteroids treatment have a lower BMD than their peers. Pediatric INS patients had a high prevalence of osteopenia and osteoporosis as measured by DEXA. Steroid therapy has a deleterious impact on bone mineralization in children with INS.

Impact of osteopenia and neutropenia in patients with colorectal cancer treated with FOLFOXIRI: a retrospective cohort study.

BACKGROUND: This study was performed to assess the impact of osteopenia on chemotherapy-induced neutropenia and the prognosis for patients treated with FOLFOXIRI for colorectal cancer. METHODS: In total, 77 patients who underwent FOLFOXIRI for un-resectable metastatic and advanced colorectal cancer were retrospectively evaluated. Osteopenia was evaluated by the bone mineral density, which was measured using the average pixel density of the trabecular bone in the 11th thoracic vertebra by computed tomography before the introduction of chemotherapy. The relationship between osteopenia and neutropenia was evaluated. Progression-free survival and overall survival of patients with osteopenia and patients with neutropenia were evaluated. RESULTS: Grade ≥ 3 neutropenia was significantly more common in patients with than without osteopenia (p = 0.002). The multivariate analysis showed that osteopenia was a significant independent predictive factor for grade ≥ 3 neutropenia (p = 0.016). There was no significant difference in progression-free survival or overall survival between patients with and without osteopenia. Patients with grade ≥ 3 neutropenia tended to have a higher progression-free survival rate than others (p = 0.059). The overall survival rate was significantly higher in patients with grade ≥ 3 neutropenia than in others (p = 0.011). CONCLUSION: Osteopenia might be a predictor of chemotherapy-induced neutropenia, and neutropenia might be a prognostic factor for progression-free survival and overall survival in patients with colorectal cancer treated with FOLFOXIRI.

Relationship of caffeine regimen with osteopenia of prematurity in preterm neonates: a cohort retrospective study.

BACKGROUND: Caffeine is a routinely prescribed pharmacological active compound in neonatal intensive care units (NICU) for treating apnea of prematurity (AOP), which also decreases the risk of bronchopulmonary dysplasia and cerebral palsy in neonates. Caffeine-induced excessive calcium loss can promote the development of metabolic bone disease (MBD) in preterm neonates. This study aimed to evaluate the effect of the caffeine regimen on the development of osteopenia of prematurity (OOP), using serum alkaline phosphatase (serum-ALP) concentrations as a surrogate marker at the 4th week of life. METHODS: This retrospective cohort study was conducted including neonates of < 32 weeks gestational age (GA) and birth weight < 1500 g, admitted to NICU from April-2017 to December-2018 and received caffeine therapy till 28 days of life for AOP. Based on serum-ALP levels, formed the high and low-ALP groups. Neonatal characteristics, caffeine regimen, risk factors for OOP, including duration of parenteral nutrition (PN), exposure to medicines associated with MBD, and intake of essential vitamins and minerals, were compared in both groups. Predictors of OOP were analyzed through logistic regression. RESULTS: From the total of 268 participants, 52 (19%) developed OOP, mostly female (61.5%). In the high ALP group, the serum-ALP levels were significantly higher than in the low-ALP group (725.0 ± 143.8 vs 273.6 ± 55.0 units/L, p < 0.001). The high-ALP group received significantly (p < 0.001) higher daily and cumulative caffeine doses and were associated with a higher likelihood of developing OOP in this study cohort [cumulative dose (mg) (AOR = 1.082 95% CI 1.011 to 1.157) and daily dose (mg/kg/day) (AOR = 2.892 95% CI 1.392 to 6.007)]. Smaller GA was found directly related to OOP. Among the other medical risk factors, phosphorus intake was significantly low in the high-ALP group. No, significant relationship between duration of PN and use of steroids and diuretics, and intake of vitamins and minerals were identified. CONCLUSION: The daily and cumulative doses of caffeine and smaller GA are associated with the development of OOP in this study cohort. Clinical randomized control studies are needed to validate the outcomes and determine the range of safest and most effective caffeine doses for treating AOP in preterm neonates.

Simplification from tenofovir disoproxil fumarate plus lamivudine or emtricitabine plus ritonavir-boosted protease inhibitor to ritonavir-boosted atazanavir plus lamivudine in virologically suppressed HIV-infected adults with osteopenia: a pilot study.

BACKGROUND: Tenofovir disoproxil fumarate, particularly when given with a ritonavir-boosted PI, reduces bone mineral density (BMD) and increases bone turnover markers (BTMs). Ritonavir-boosted atazanavir plus lamivudine is a feasible simplified option. We evaluated whether switching from a triple ritonavir-boosted PI plus tenofovir disoproxil fumarate to a two-drug regimen of lamivudine plus ritonavir-boosted atazanavir would improve BMD. METHODS: Single-arm pilot study. Virologically suppressed patients on tenofovir disoproxil fumarate plus lamivudine or emtricitabine plus ritonavir-boosted PI with low BMD, without previous resistance mutations and/or virological failure to study drugs were switched to 100/300 mg of ritonavir-boosted atazanavir plus 300 mg of lamivudine once daily. The primary endpoint was BMD change by DXA at Week 48. RESULTS: There were 31 patients, 4 (13%) female, and median age was 40 years. Seven participants (22.5%) had osteoporosis. At 48 weeks, mean (SD) changes in spine and hip BMD were +0.01 (0.03) (P = 0.0239) and +0.013 (0.03) g/cm2 (P = 0.0046), respectively. Mean (SD) T-score changes were +0.1 (0.23) (P = 0.0089) and +0.25 (0.76) (P = 0.0197), respectively. N-telopeptide and urine tenofovir disoproxil fumarate toxicity markers showed significant improvements. One participant withdrew from the study and two were lost to follow-up. There were no virological failures, or serious or grade 3-4 adverse events. CONCLUSIONS: Switching from a tenofovir disoproxil fumarate plus ritonavir-boosted PI triple therapy to a lamivudine plus ritonavir-boosted atazanavir two-drug regimen in virologically suppressed HIV-infected adults with low BMD was safe, increased low BMD and reduced plasma markers of bone turnover and urine markers of tenofovir disoproxil fumarate toxicity over 48 weeks.

Bone Mineral Density Assessment by Quantitative Computed Tomography in Glucocorticoid-Treated Boys With Duchenne Muscular Dystrophy: A Linear Mixed-Effects Modeling Approach.

Objective: Boys with Duchenne muscular dystrophy (DMD) are at risk of bone damage and low bone mineral density (BMD). The aim of the study is to examine lumbar BMD values measured by QCT and identify the factors associated with BMD loss using a multilevel mixed-effects model. Methods: Lumbar BMD was evaluated by quantitative computed tomography (QCT) at diagnosis, 1 and 2 years follow up in patients with DMD who were treated with GC. Demographic data, functional activity scores (FMSs), laboratory parameters and steroid use were recorded. A multilevel mixed-effects model was used to analyze BMD loss. Results: Nineteen patients with DMD who had a total of sixty complete records between January 2018 and October 2021 were retrospectively analyzed. At baseline, 15.8% of patients (3/19) had low lumbar BMD (Z score ≤ -2), and the mean BMD Z score on QCT was -0.85 (SD 1.32). The mean BMD Z score at 1 and 2 years postbaseline decreased to -1.56 (SD 1.62) and -2.02 (SD 1.36), respectively. In our model, BMD Z score loss was associated with age (ß=-0.358, p=0.0003) and FMS (ß=-0.454, p=0.031). Cumulative GC exposure and serum levels of calcium, phosphorus, 25(OH)-vitamin D and creatinine kinase did not independently predict BMD loss. Conclusions: This study demonstrates that in DMD patients, lumbar BMD decreased gradually and progressively. Age and FMS are the main contributors to BMD loss in boys with DMD. Early recognition of risk factors associated with BMD loss may facilitate the development of strategies to optimize bone health.

Plasma metabolomics study reveals the critical metabolic signatures for benzene-induced hematotoxicity.

Metabolomics has been used to explore the molecular mechanism and screen biomarkers. However, the critical metabolic signatures associated with benzene-induced hematotoxicity remain elusive. Here, we performed a plasma metabolomics study in 86 benzene-exposed workers and 76 healthy controls, followed by a validation analysis in mice, to investigate the dynamical change of the metabolic profile. We found that 8 fatty acids were significantly altered in both benzene-exposed worker and benzene-exposed animal models. These metabolites were significantly associated with S-phenylmercapturic acid and WBC, and they mediated the benzene-induced WBC decline. Furthermore, in vivo results confirm that fatty acid levels were dynamically altered, characterized by a decrease at 15 days and then sharp increases at 30 and 45 days. Following these identified fatty acids, the potential metabolic pathways were investigated. Fatty acids, as precursors for fatty acid oxidation, may disturb the balance of fatty acid biosynthesis and degradation. Our results reveal that fatty acid metabolism was strongly reprogrammed after benzene exposure. This abnormal change of fatty acids might be the key metabolic signature associated with benzene-induced hematotoxicity.

Association between Bone Morphogenetic Protein 2 Gene Polymorphisms and Skeletal Fluorosis of The Brick-tea Type Fluorosis in Tibetans and Kazakhs, China.

To investigate the potential association between BMP2 single nucleotide polymorphisms (SNPs) and brick-tea-type skeletal fluorosis risk in cross-sectional case-control study conducted in Sinkiang and Qinghai, China, a total of 598 individuals, including 308 Tibetans and 290 Kazakhs, were enrolled. Using the standard WS/192-2008 (China), 221 skeletal fluorosis cases were diagnosed, including 123 Tibetans and 98 Kazakhs. Logistic regressions 2 analysis did not find the association between SNPs (Rs235764, Rs235739 and Rs996544) and skeletal fluorosis. Genetic models, linkage disequilibrium (LD) and haplotype analysis were not found to be associated with risk of skeletal fluorosis after adjustment by age and sex (P>0.05).Our data suggested that Rs 235764, Rs 235739 and Rs 996544 were not linked susceptibility for skeletal fluorosis in our cross-sectional case-control study.

Is There an Association Between Bone Microarchitecture and Fracture in Patients who were Treated for High-grade Osteosarcoma? A Controlled Study at Long-term Follow-up Using High-resolution Peripheral Quantitative CT.

BACKGROUND: Neoadjuvant chemotherapy in patients with primary osteosarcoma improves survival rates, but it also causes side effects in various organs including bone. Low bone mineral density (BMD) can occur owing partly to chemotherapy or limited mobility. This can cause a higher risk of fractures compared with those who do not receive such treatment. Changes in BMD alone cannot explain the propensity of fractures. Studying microarchitectural changes of bone might help to understand the effect. QUESTIONS/PURPOSES: (1) Do patients who were treated for osteosarcoma (more than 20 years previously) have low BMD? (2) Do these patients experience more fractures than controls who do not have osteosarcoma? (3) What differences in bone microarchitecture are present between patients treated for high-grade osteosarcoma and individuals who have never had osteosarcoma? METHODS: We contacted 48 patients who were treated for osteosarcoma and who participated in an earlier study. These patients underwent multimodal treatment including chemotherapy more than 20 years ago. Of the original patient group, 60% (29 of 48) were missing, leaving 40% (19 of 48) available for inclusion in this study; all 19 agreed to participate. There were nine men and 10 women with a mean age of 46 ± 4 years and a mean time from surgery to examination of 28 ± 3 years. BMD was measured by dual-energy x-ray absorptiometry, and any fracture history was assessed using a questionnaire. Additionally, high-resolution peripheral quantitative CT was performed to compare the groups in terms of microarchitectural changes, such as cortical and trabecular area, cortical and trabecular thickness, cortical porosity, and endocortical perimeter. Participants in the control group were selected from a cohort consisting of a population-based random sample of 499 healthy adult women and men. Osteoporosis or low BMD was not an exclusion criterion for entering this study; however, the patients in the control group were selected based on a normal BMD (that is, T score > -1.0 at both the spine and hip). Also, the participants were matched based on age and sex. Differences between patients and controls were assessed using the Wilcoxon rank sum test for continuous variables and a chi-square test for categorical variables. A multiple regression analysis was performed. Model assumptions were checked using histograms and quantile-quantile plots of residuals. RESULTS: Twelve of 19 patients who were treated for osteosarcoma had either osteopenia (eight patients) or osteoporosis (four patients). More patients with osteosarcoma reported sustaining fractures (11 of 19 patients) than did control patients (2 of 19 controls; p < 0.001). Among all microarchitectural parameters, only the endocortical perimeter was increased in patients compared with the control group (75 ± 15 mm versus 62 ± 18 mm; p = 0.04); we found no differences between the groups in terms of cortical and trabecular area, cortical and trabecular thickness, or cortical porosity. CONCLUSION: Although patients who were treated for osteosarcoma had osteopenic or osteoporotic BMD and a higher proportion of patients experienced fractures than did patients in the control group, we could not confirm differences in microarchitectural parameters using high-resolution peripheral quantitative CT. Therefore, it seems that bone geometry and microstructural parameters are not likely the cause of the increased proportion of fractures observed in our patients who were treated for osteosarcoma. Until we learn more about the bone changes associated with chemotherapy in patients with osteosarcoma, we recommend that patients undergo regular BMD testing, and we recommend that physicians consider osteoporosis treatment in patients with low BMD. These data might provide the impetus for future multicenter prospective studies examining the association between chemotherapy and bone microarchitecture. LEVEL OF EVIDENCE: Level III, therapeutic study.

Omega-3 fatty acid-rich fish oil supplementation prevents rosiglitazone-induced osteopenia in aging C57BL/6 mice and in vitro studies.

Rosiglitazone is an effective insulin-sensitizer, however associated with bone loss mainly due to increased bone resorption and bone marrow adiposity. We investigated the effect of the co-administration of fish oil rich in omega-3 fatty acids (FAs) on rosiglitazone-induced bone loss in C57BL/6 mice and the mechanisms underlying potential preventive effect. Mice fed the iso-caloric diet supplemented with fish oil exhibited significantly higher levels of bone density in different regions compared to the other groups. In the same cohort of mice, reduced activity of COX-2, enhanced activity of alkaline phosphatase, lower levels of cathepsin k, PPAR-γ, and pro-inflammatory cytokines, and a higher level of anti-inflammatory cytokines were observed. Moreover, fish oil restored rosiglitazone-induced down-regulation of osteoblast differentiation and up-regulation of adipocyte differentiation in C3H10T1/2 cells and inhibited the up-regulation of osteoclast differentiation of RANKL-treated RAW264.7 cells. We finally tested our hypothesis on human Mesenchymal Stromal Cells differentiated to osteocytes and adipocytes confirming the beneficial effect of docosahexaenoic acid (DHA) omega-3 FA during treatment with rosiglitazone, through the down-regulation of adipogenic genes, such as adipsin and FABP4 along the PPARγ/FABP4 axis, and reducing the capability of osteocytes to switch toward adipogenesis. Fish oil may prevent rosiglitazone-induced bone loss by inhibiting inflammation, osteoclastogenesis, and adipogenesis and by enhancing osteogenesis in the bone microenvironment.